Reflections of a Summer Observer
2007-06-18 06:47:04.000 – Jon Cotton, Observer
Thin Wave Stratus
Recently returned from a glorious vacation (the first in a year and a half), I’m ready to add some thoughts to these here comments. Regular readers can already see how much change is happening as summer settles in. I’ve got new Observer coworkers, new intern comrades and brand-new first time volunteers are arriving for week long experiences. The Mt Washington Auto Road has hosted a slew of events including but not limited to Bike Day, a second Bike Day, the Foot Race, Alternative Energy Vehicle Day, a Mini Cooper fleet sunset trip and probably some other hot tickets that I missed while out of state. The sedge is green and both diapensia and lapland rosebay are colorfully dotting the tundra. I’m sure more are in flower for those venturing further afield in the alpine zone. The AMC Huts are open full service with meals and entertainment. The Randolph Mountain Club shelters are warm once again and of course welcoming guests. Crowds of people are enjoying the weather. Every night I find a few discarded water bottles blowing around the deck. Actually two nights ago I found an unopened water that provided welcome relief in the sweltering midnight hours. Night observers often suffer parched throats and moonburn – I know, little known fact but one of the Observatory’s missions is education so there you go.
Every Wednesday we have a shift change meeting to plan progress. One recurring topic in the last couple months is improving our forecast accuracy. Brent Antkowiak, a winter intern, compared a full year of forecasts to the actual weather observed. Keep in mind the Observatory only started its 36-hour mountain forecast two years ago. Brent examined the four seasons of 2006 to determine how well we did at forecasting for temperature, wind speed, precipitation and sky condition over the 12/24/36 hour intervals. One conclusion that perked all our ears was how difficult a sky condition forecast is during the summer months. Which is to say, how many clouds are going to clutter the sky and will there be fog on the peaks? The challenge is convective heating causing cumulus development balanced with existing instability. An extension to this is thunderstorm prediction. These are atmospheric conditions that we simply don’t have to deal with in the winter. In the words of GI Joe, “knowing is half the battle”.We have new and improved forecast tools to ply our trade. We know what to be aware of. One summer intern project will be specifically to study, test and verify these new methods with our sky condition accuracy.
At any rate, this single week has been unlike every other week this winter. Saturday night from 11 pm until I went to sleep at 6am, I watched a thunderstorm amble out to the northwest and monitored the lightning strike records on the radar. Looking out the window I could see mostly in-cloud lightning, occasionally the clouds would shift enough to give me a view of ground strikes over the VT-NH border and twice fog blew in where all I could see were the flashes. It was an interesting storm to watch because the summit was in the clear with stars above. The mountain was in a different pocket of weather with a clear view of its neighbors. Around 3am, the storm arrived over Whitefield, it nudged closer, it wrapped the summit in fog and then 20 minutes later it had completely hopped over the mountain range landing to the east. We received a total of 15 minutes rain. Whitefield and the northern sky was free of dark clouds and starting to let the sunrise in. From my vantage point, the entire sky from west through south to east – 180 degrees – was now dark with rain lit only with occasional lightning. The radar showed a storm that had broken around the mountain continuing mostly on an altered course to the south with the weaker component that had hopped over to the east. When I started my next shift at 4:30pm the same day, a new storm was throwing lighting in Maine to the northeast. Watching – literally watching – these tight pockets of thunderstorm negotiate the countryside is fantastic.
Forecasting this requires new skills. New model variables must be heeded. I’m using the same tools with different information overlays while comparing the National Weather Service discussions with what the models show me will happen around northern NH. I interpret and write the forecast that gets posted on the website and broadcast over radio. Already I’m using different language in the summit outlook discussion and highlighting significant cloud development that just isn’t applicable in the winter. In a nutshell, whether you are aware or not, you have seen the summer clouds I’m talking about. Read at least the start of this Environment Canada page and click on the images for a visual.
Another interesting phenomena occurred this morning around sunrise. The inset photograph shows an incredibly thin wave-formed stratus that extended from Mount Clay all the way off to at least 30 miles into Maine. What was remarkable about this is how persistent and stable this cloud veil was. You can see multiple waves twisting in and out of other waves creating something that probably has a geometric name. These twists would slightly shift; at times the clear defined bottom edge would mirror up to four times. The really remarkable thing is that this condition lasted an hour and a half in basically the same configuration. Actually it roughly lasted three hours but once a very thick layer of haze choked out the horizon it sort of broke up into chunky brown blocks hovering at different levels of air – more like flotsam hanging on the lines of previously pristine waves of air.
There is more to say about this because it provides a good segway into one of my favorite topics – air quality. This stuff is important so it deserves its own comment. In the meantime, there is one more thing to report from the Seasonal Changes of Mt Washington News Department. The State Park assures me that while the soft-serve ice cream machine is currently down it will be operational soon.
Oh and happy Monday. Welcome back to the work week.
Jon Cotton, Observer